The Brown Superfund Research Program (SRP)-Toxicant Exposures in Rhode Island: Past, Present, and Future-uses its highly successful paradigm of academic-government-community partnerships to tackle environmental health and remediation concerns in Rhode Island, an appropriate geopolitical context for interdisciplinary initiatives. This partnerships model resolves the longstanding problem of how to bring affected parties together to address issues of site contamination by complex mixtures. The scientific theme for this re-submission is Integrated Biomedical & Engineering Solutions to Regulatory Uncertainty, pursued by four projects (two biomedical and two engineering/environmental science) tackling complex issues of past, present and future environmental degradation resulting from legacy chemicals, current discharges, and emerging contaminants. This state-of-the-art research effort addresses key scientific uncertainties facing the Superfund program using the latest research tools, approaches, and technologies in Biomedical-Engineering Project Collaborations (Vapor Intrusion Modeling and Health Monitoring, Nanotechnology Applications and Safety), and within-discipline integration (Biomarkers & Toxicity Testing, Nanomaterial Vapor Barriers). State Agencies Liaisons in Engineering and Environmental Health are a unique feature of the Brown SRP. These positions have enabled the Research Translation Core and Community Engagement Core to develop academic-government-community partnerships with hazardous waste sites contaminated with mixtures of toxicants, both Superfund sites (Centredale Manor Restoration Project, Peterson/Puritan) and Brownfields sites (Fisherville Mill, Gorham/Textron/Mashapaug Pond, Industrial Lane Johnston, and Narragansett Tribal Lands/Waters). The Administrative Core, Training Core, and Molecular Pathology Core support interdisciplinary research and training involving these sites and their contaminants. The Brown SRP provides Rhode Islanders with a responsive center of technical excellence that takes a research-oriented approach to resolving the complex scientific, engineering, and societal issues that are associated with the remediation of hazardous waste sites, by focusing on the following Specific Aims: Specific Aim 1: Build on existing strong academic-government-community partnerships to address local environmental health and contaminant remediation issues as a national model of effective intervention at Superfund and Brownfields sites. Specific Aim 2: Discover innovative scientific solutions to regulatory uncertainty and environmental contamination by working at the biomedical-engineering interface. Specific Aim 3: Pursue interdisciplinary approaches to research, training, and communication to maximize the value and impact of our work locally and nationally.